An electrical steering system of a motor vehicle generally comprises an electromechanical actuator which is located on the steering column or on the lower assembly which comprises mechanical members which are intended to ensure the angular positioning of the guiding wheels of the vehicle. The electromechanical actuator comprises a rotational electric motor, whose shaft is supported by at least one rolling bearing, directly or via a system of ballscrews. The rolling bearing generally comprises an inner ring, an outer ring and a row of rolling elements, generally balls, which are arranged between the rings.
The document FR-A1-2 911 934 discloses a retention cage for a rolling bearing comprising a plurality of identical pockets for receiving balls, which pockets are each partially defined by two claws which are arranged opposite a projection of the cage. Such cages are completely satisfactory in a large number of applications. However, in applications at a low rotation speed or for which the direction of rotation is reversed abruptly, this type of cage involves various difficulties. This is because, under the effect of the balls, the cage may become powerfully deformed and come into contact with the inner ring, which causes damage thereto or the destruction thereof.
Furthermore, during a change in direction of the load applied to the rolling bearing, such as, for example, during the steering of the wheels of a vehicle provided with an electric steering system when the driver carries out maneuvers towards the left and towards the right in order to park the vehicle, the cage is also powerfully deformed, or destroyed, by the instantaneous increase in the torque.
The document FR-A1-2 883 941 also discloses a cage for a rolling bearing comprising first pockets which are provided with axial retention claws for the cage on the balls and second pockets which do not have retention claws.
With such a cage, there may be brought about an axial separation of the cage in relation to the balls.